(1) Field of the Invention
The present invention relates to a trailer, such as a caravan, having a chassis and at least one wheel axle provided with wheels, as well as a manoeuvring device fitted close to a wheel for manoeuvring said trailer when the latter is in the uncoupled state.
(2) Description of the Related Art
A manoeuvring device of this type is generally known in the state of the art. Especially for manoeuvring heavier trailers and heavier caravans, if these have been uncoupled from the towing vehicle, constructions are used where rollers are pushed against the tyres of the wheels and are then driven round. In this way a heavy trailer can be moved independently of the towing vehicle.
If vehicles are even heavier, tandem axles are used. In order to manoeuvre such a vehicle and in particular to turn it, particularly high resistance is encountered from the non-steerable wheels of the tandem axle which are located close together. It has been found that it is not possible under all circumstances to achieve such rotation using a single motor engaging on a wheel.
An alternative would be the use of two drive rollers per side, which is found not to function in practice and is associated with appreciable costs.
U.S. Pat. No. 4,616,726 shows an articulated vehicle, wherein the rear wheels can be lifted with a lifting arm system, such that non-driven rollers engage the soil. The axis of these rollers is under an angle with the axis of the wheels, such that easy turning of the vehicle can be effected. Drive is through the front wheels.
GB 2 199 793 shows a vehicle having near its front thereof a manoeuvring device comprising a central roller to be placed between the front wheels of the vehicle and in front of those wheels. Drive is through the rear wheels. Only a single roller is used.
Neither U.S. Pat. No. 4,616,726 nor GB 2 199 793 gives a solution for the problem to rotate a tandem axled trailer.
The aim of the present invention is to avoid these problems and to provide a construction with which it is possible to manoeuvre a single- or double-axled trailer such as a caravan that has been uncoupled from a towing vehicle, including in those cases where the substrate is relatively unstable.